Chronic Obstructive Pulmonary Disease (COPD)
COPD is a progressively debilitating disease affecting an estimated 16 million Americans. In 1984, COPD ranked fifth as the leading cause of death in the United States. From a disability standpoint, COPD is the most frequent reason that people seek medical attention (1).
It has been found that there is a direct relationship between body weight and respiratory muscle mass (2) and that a significant percentage of patients with COPD are malnourished (1, 2). Epidemiologic surveys of COPD have suggested that undernutrition might be an important prognostic variable (2). When the COPD patient begins to lose weight, the average life expectancy is only 2.9 years (1).
Disabilities in patients with COPD due to limitations in pulmonary function are often compounded by a loss of muscle strength and lean body mass, resulting in an inability to perform many activities of daily living. These losses may be attributable to a number of factors including decreased ability to exercise, decreased appetite, hypermetabolism and protein catabolism resulting from prolonged glucocortoid therapy. Because of undue dyspnea, these patients are frequently afraid to exercise, which exacerbates their muscle wasting condition. Shortness of breath during eating also worsens this condition because it leads to inadequate calorie and protein intake. Furthermore, many of these patients are receiving intermittent or chronic treatment with anti-inflammatory steroids that may result in myopathy, especially causing weakness in the proximal lower extremities. A combination of these factors often contribute to disability in patients with COPD that exceeds what would generally be expected based on airflow limitation alone.
Because of the progressive decline due to dyspnea and cachexia in these patients, levels of morbidity and mortality exceed those expected based on pulmonary limitations alone.
The subject invention provides therapies to reverse or halt the catabolic process and restore lean body mass in COPD patients. The subject invention also provides therapies to improve functional capacity and/or pulmonary function in these patients.